The Sky in December

Some Bright Autumn Double Stars

October 2005 : By Glenn Chaple

Autumn is a season of promise for the stargazers. The nights are getting longer, the air clearer, and those pesky summer mosquitoes are a thing of the past. In a few months, Orion and his magnificent wintry retinue will take center stage. While the autumn night sky appears devoid of bright stars, it’s still home to a rich array of double stars. Here are ten of the best:

Some Bright Winter Double Stars

December 2005 : By Glenn Chaple

The winter night sky, dominated by mighty Orion, is rich with deep-sky splendors. If you can brave the cold, you’ll be rewarded by some of the finest double and triple stars the night sky has to offer.

A Selection of Double Stars in Orion

January 2007 : By Glenn Chaple

Of the one hundred double and multiple stars on the Astronomical League’s double stars list, nine are found in Orion.

M74: Galaxy in Pisces

January 2012 : By Glenn Chaple

Last month, we explored the galaxy M33, a notoriously difficult telescopic target due to its extremely low surface brightness. For the same reason, M74 is even more challenging; in fact, many consider it the most visually demanding of all the Messier objects.

A Selection of Double Stars in Gemini

January 2008 : By Glenn Chaple

It’s appropriate that the constellation Gemini, the Twins, should be home to a numerous collection of double stars. Here are ten stellar – pardon the pun - examples (data from the Washington Double Star Catalog (WDS).

A Selection of Double Stars in Andromeda

November 2008 : By Glenn Chaple

Andromeda is home to a fine collection of double stars. Here are eight of the best. Data on magnitudes and separation were taken from the Washington Double Star Catalog.

Struve 817 Orionis

January 2009 : By Glenn Chaple

I’m a big fan of “off-the-beaten-path” sky objects. One of my favorites is the little-known double star Struve 817 - the 817th double star catalogued by the German-born Russian astronomer F. G. W. Struve during a survey conducted between 1824 and 1827.

A White Dwarf You can Actually See!

February 2009 : By Craig Cortis

A double star in Eridanus contains a white dwarf star that is easy to locate and see with small telescopes.

The Winter Circle

February 2009 : By Dave Huestis

Just as the summer sky has the Summer Triangle, the winter sky has its own special asterism, and this one is huge and includes a total of eight bright stars. It’s called the Winter Circle or Winter Hexagon. I’ll explain why you can get both shapes from the stars.

NGC 2362: Open Cluster in Canis Major

March 2009 : By Glenn Chaple

A remarkable, yet little-known open cluster is NGC 2362 which surrounds and includes the star tau Canis Majoris.

Epsilon Pegasi: The Pendulum Star

September 2009 : By Glenn Chaple

Epsilon Pegasi (Enif) is an optical double star comprised of magnitude 2.5 and 8.7 component stars separated by 144 seconds of arc. Pairs this wide usually don’t merit much consideration, but wait! Epsilon Pegasi has a surprise for us.

Beta Persei (Algol, the "Demon Star")

November 2009 : By Glenn Chaple

Are you ready for the eclipse of November 13th? I’m not talking about the sun or moon. I’m referring instead to an eclipse of the fascinating star ß Persei (Algol).

NGC 7293: the Helix Nebula

October 2009 : By Glenn Chaple

NGC 7293, the Helix Nebula, is the nearest planetary nebula (distance ~ 450 LY) and largest in apparent size (12 by 16 arcminutes). Moreover, it’s a 7th magnitude object. An easy telescopic target? Hardly! The magnitudes listed for deep-sky objects are often misleading, and the Helix Nebula is a prime example.

h 3945 Canis Majoris

March 2010 : By Glenn Chaple

What is the most colorful double star in the night sky? Most amateur astronomers would vote for β Cygni (Albireo). Others might cite γ Andromedae (Almach), ι Cancri, ξ Bootis, or η Cassiopeiae. Sadly overlooked is a double star that might challenge them all – h 3945 in Canis Major. It is arguably the most colorful double star in the winter sky and, in fact, has been nick-named the “Winter Albireo.”

Beta Orionis (Rigel)

February 2010 : By Glenn Chaple

You won’t need a finder chart to locate this month’s featured sky object. It’s the first magnitude star β Orionis, better known by its proper name Rigel. Seventh brightest star in the night sky, Rigel dazzles us with a diamond-white color; especially striking when compared with Orion’s other first-magnitude star, the ruddy-hued Betelgeuse.

Omicron Ceti (Mira, the “Wonderful”)

January 2010 : By Glenn Chaple

Last month, we looked at the prototypical eclipsing binary beta Persei (Algol). This month, we turn to another prototype, the classic long-period variable (LPV) omicron Ceti.

Castor: alpha (α) Geminorum

March 2011 : By Glenn Chaple

Are you looking for something new and different to add to your late winter/early spring star party repertoire – a cosmic showpiece guaranteed to elicit a gasp of surprise and wonder from anyone who peers into your telescope? I suggest the double star alpha (α) Geminorum, better know as Castor. One glance at these sparkling magnitude 2.0 and 2.9 diamonds and it’s easy to understand why William Herschel’s son, John, considered Castor the finest double star in the northern sky.

NGC 457 (the “ET Cluster”)

December 2010 : By Glenn Chaple

Have you seen “ET” lately? Not that cute little alien in Steven Spielberg’s 1982 movie. I’m referring to the ET-mimicking open star cluster NGC 457 in Cassiopeia. Discovered by William Herschel in 1787, NGC 457 is often overlooked because of its proximity to the Messier cluster M103.

Orion the Hunter

February 2011 : By Dave Huestis

Everyone with an interest in astronomy probably has a favorite constellation. It may be because of the star pattern’s mythology, or its shape in the sky, or for the beautiful objects that reside within its boundaries, or possibly because it’s your astrological sign.

β Monocerotis

February 2011 : By Glenn Chaple

Observe one of the sky's best triple stars just 12 degrees east of the Great Orion Nebula.

Observe Delta Cephei

December 2011 : By Gerry Dyck

Gerry Dyck introduces us to variable star observing with the naked eye star Delta Cephei.

December Constellations & Folklore

December 2011 : By Francine Jackson

Orion and Gemini move into their dominant positions as winter begins.

M33: Galaxy in Triangulum

December 2011 : By Glenn Chaple

Consider the spiral galaxy M33 in Triangulum. Listed as a 6th magnitude object, it’s notoriously difficult to view in telescopes. M33 is elusive because its light is spread over an area four times that of the full moon.

December Long Night Moon

December 2012 : By Francine Jackson

With the winter season beginning this month, the nights are the longest, and the days slowly begin to get colder. As such, we celebrate both the Full Cold Moon and the Full Long Night Moon. And, because we also celebrate the holiday season at this time of year, this can also be called the Moon Before Yule, although this year it takes place afterwards, on December 28th.

M78: Reflection Nebula in Orion

March 2013 : By Glenn Chaple

It’s understandable that M78 should be overlooked by backyard astronomers. Not far away is the much brighter, much more easily found, and much, much more spectacular M42 - the Orion Nebula. This deep-sky masterpiece was spectacular even through the eyepiece of my 3-inch scope. M78, on the other hand, was a faint blob that seemed to sport an off-center nucleus.